Everywhere: Add sv suffix to strings relying on StringView(char const*)

Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).

No functional changes.

Userland/Libraries/LibGUI/Application.cpp

@@ -28,7 +28,7 @@ public:
     {
         m_label->set_text(Gfx::parse_ampersand_string(tooltip));
         int tooltip_width = m_label->effective_min_size().width().as_int() + 10;
-        int line_count = m_label->text().count("\n");
+        int line_count = m_label->text().count("\n"sv);
         int glyph_height = m_label->font().glyph_height();
         int tooltip_height = glyph_height * (1 + line_count) + ((glyph_height + 1) / 2) * line_count + 8;